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Questions in chemistry

[Done] Given the balanced equation representing a reaction: \[ H_2O + HCl \rightarrow H_3O^+ + Cl^- \] According to one acid-base theory, the \( H_2O \) molecule: 1. accepts \( H^+ \) ions 2. accepts \( OH^- \) ions 3. donates \( H^+ \) ions 4. donates \( OH^- \) ions

[Done] In terms of entropy and energy, systems in nature tend to undergo changes toward: 1. lower entropy and lower energy 2. lower entropy and higher energy 3. higher entropy and lower energy 4. higher entropy and higher energy

[Done] Which term identifies a type of organic reaction? 1. Deposition 2. Distillation 3. Esterification 4. Sublimation

[Done] Which compounds are classified as Arrhenius acids? A. HCl and NaOH B. HNO3 and NaCl C. NH3 and H2CO3 D. HBr and H2SO4

[Done] Which element reacts spontaneously with 1.0M HCl (aq) at room temperature? A. Copper B. Gold C. Silver D. Zinc

[Done] Which term represents a type of nuclear reaction? 1. condensation 2. vaporization 3. single replacement 4. natural transmutation

[Done] The accepted value for the percent by mass of water in a hydrate is 36.0%. In a laboratory activity, a student determined the percent by mass of water in the hydrate to be 37.8%. What is the percent error for the student's measured value? (1) 5.0% (2) 4.8% (3) 1.8% (4) 0.05%

[Done] Which condensed structural formula represents an unsaturated compound? 1. CH3CH=CHCH3 2. CH3CH2CH3 3. CH3CH3 4. CH4

[Done] Given the balanced ionic equation: \[ 3\text{Pb}^{2+} + 2\text{Cr} \rightarrow 3\text{Pb} + 2\text{Cr}^{3+} \] What is the number of moles of electrons gained by 3.0 moles of lead ions? 1. 5.0 mol 2. 2.0 mol 3. 3.0 mol 4. 6.0 mol

[Done] Which formula represents an organic compound? 1. CaH₂ 2. C₄H₈ 3. H₂O₂ 4. P₂O₅